I just wanted to chime in to say - I've played Star Fox Zero, and even though I'm usually pretty cynical about most things Wii U, I actually had a lot of fun playing it. It looked a bit dated sure, but it kinda felt intentional, like they were going for a retro arcadey look. It also felt like one of those games that's fun enough for you not to care too much about that, and it ran really smoothly for it.
I think if you're annoyed that it's not blistering new detail rich visuals that make full use of your telly instead of the gamepad you're kinda missing the point of the title. I feel the opposite about things like Zelda, Metroid, Mario, where scale and immersion are huge factors, but a game like Star Fox should focus on the fun and challenge factor above all else.